The Little Fire ant Wasmannia auropunctata (Roger) (Hymenoptera: Formicidae) as a Diversity Indicator of Ants in Tropical Dry Forest Fragments of Colombia

Ant richness within 14 Colombian dry forest fragments varies from at least 34Ð128 species.Wehave collected the little Þre ant,Wasmannia auropunctata (Roger) in each of the fourteen forest fragments, bymeansof tunabaits, pitfall traps, samplingof logs, understory vegetation and forest litter sampling. A highly signiÞcant negative relation was found between the percentage of W. auropunctata samples per forest fragment and richness for the ant community. Additionally, a signiÞcant positive relationship was found between the abundance of W. auropunctata and the number of ant-plant associations in nine of the forest fragments. The displacement of other ants by W. auropunctata could be explained in terms of its competitive performance, natural history and ability to exploit disturbed sites. This opportunistic species displays high interspeciÞc aggressiveness, recruiting workers massively to a variety of food resources. It also colonizes different substrates and formsunicolonial societies,whichdispersebroadlybydetachinggroupsofworkers alongwithmultiple queens. The species can be easily monitored with tuna baits, which showed the same signiÞcant negative relation. We propose that the abundance of the little Þre ant can be used as an indicator of low diversity ant communities in dry forest fragments of the Cauca river valley of Colombia.